1. Field of the Invention
This invention is generally related to inhibiting the removal of cable or wire from a conduit. More particularly, embodiments of the present invention pertain to apparatuses, systems and methods for applying a restraining load to one or more wires or cables resulting in the prevention of unwanted theft or removal of such wires or cables from the conduit.
2. Background and Description of Related Art
Wire and cable are widely used for the communication of signals. Wire can be formed from different materials such as metals, plastics, or ceramics, each of which are particularly suited for the efficient transmission of different signals, e.g. metal conducts electrical signals, glass conducts light signals, etc. Although a cable generally contains numerous individual strands of wires, some cables can include a single strand of wire. While this disclosure will particularly refer to cables comprising multiple metal wires, given its importance in the context of contemporary applications, it is to be appreciated that the instant invention may also be useful for hindering removal of wires or cables made from other well-known materials or materials yet to be discovered or widely used in industry.
A common metal used in the manufacture of electrical wire is copper. As the market value of copper and other metals used for the manufacture of wire increases, the rate of wire theft also tends to increase. Stolen wire can be redeployed in another application, or most commonly, sold as raw material in the original or a modified form for a profit. Unfortunately, due to the ease of access to electrical wires, the ease of processing the wire to a different form, and the difficulty in tracking the metal origin, this is a very difficult crime to prevent and solve.
One easily accessible source of wire for wire theft are electrical pull boxes which are commonly utilized in most communities in the United States and throughout the world. Electrical pull boxes generally have a box-like configuration with a removable lid and one or more conduit entry points to receive wire into the inner chamber defined by the walls and lid of the pull box. The typical electrical pull box may be configured to receive wire into the chamber through one or more sides of the pull box and allows wire to exit the chamber through one or more of the sides. The incoming wires can be connected to the outgoing wires in the chamber. In the typical configuration, the incoming and outgoing wires are disposed in appropriately configured and sized conduits to protect the wire from exposure to the elements and to reduce the likelihood of damage or other mishap which may cause a disruption in the transmission.
Pull boxes are attractive targets for thievery since they are typically located in areas that can be accessed discretely. Since the wires are generally free, i.e. unsecured within the pull box or conduit, they can be removed relatively easily; all the thief has to do is to take the pull box lid off, cut the wires at their connection and then pull on the wires to remove them from the conduit.
Another target of wire theft is wires or cables which are disposed within a tubular conduit. The conduit provides protection to the wires or cables within the conduit from the elements and the surrounding environment. In some examples, the conduit may be placed underground while in other examples the conduit may be disposed above ground. In yet other examples, the conduit may be disposed inside portions of a building, such as in the rafters, basement, or between the walls. In some implementations, the conduit may have a significantly long length, for example over one hundred meters. Sometimes, then, the conduit may comprise multiple sections of conduit that are connected end to end.
Underground wire is typically stolen by a thief grasping an end of the wire or cable by hand and pulling it from the conduit. In other examples, underground wire can be stolen by first attaching one end of the wire or cables to a traction device such as the tow-bar of a sufficiently powerful vehicle. The vehicle is usually driven away, pulling the cable in an axial direction and removing it from the conduit. Frequently such thefts are carried out on newly laid cables, or cables that have been partially laid such that an end is easily accessible. Nonetheless, when the wires are not easily accessible, the thief may dig toward the underground wire conduit in order to free a wire end to allow for removal as described above.
Wire theft represents a sizable cost both to the owner and to society at large. To the owner, in addition to the cost of replacing the wire, there is additional labor and equipment costs associated with installing the replacement wire. These costs can run into the hundreds of dollars, and in some instances, thousands of dollars. To a society, the unauthorized removal of wire may disrupt community power, communications, etc. It can also result in an increased risk of harm to the person or property of those affected by the disruption. Further, these disruptions may lead to a general reduction in the productivity and well-being of the society.
Over the years, various devices have been developed to deter or prevent theft of wire or cable from a conduit. For instance, U.S. Patent Application Publication No. 2007/0020974 to Carlson discloses a tamper resistant plug configured to prevent unauthorized persons from pulling wires out of a conduit. Further in the art, WIPO Patent Publication No. 02/073762 to Theron, et al., discusses a method of combating the theft of an underground cable in which there is secured to the outside surface of a cable, at spaced intervals along the length thereof, a series of obstructive elements, each of which, engages the outer surface of the cable either frictionally or physically. However, the devices disclosed in each of these references are inadequate in that they apply retention force in the same direction as the removal force. As such, when a removal force in the axial direction exceeds the retention force, the wire or cable may be removed.
Therefore, there is a need for apparatuses, systems and methods that can effectively and economically restrain or hinder the rapid removal of one or more wires or cables within a conduit, thus deterring theft of such wires or cables.